DSA Laptop Upgrade?

Well I would go for the Sony, because its far more reliable and I expect better battery life.

I would ignore the pc world rep's advice
The Sony is actually not more powerful, in fact slightly weaker it has a ultrabook cpu "u" rather then the standard laptop one "m".
Generally speaking, Acer is in the bottom end of reliability..........whereas the Sony isn't and the fact it utilises a ultrabook cpu means quite power efficient and looking up, up to about 5 hours battery life.

Other things to note is that the Sony cpu is a 3rd gen cpu rather then a 2nd gen on the Acer, meaning slightly improved processing, and integrated graphics is significantly different to the old one with a HD4000.

Do they not have other options?

The Acer is a good all-round basic laptop and would probably be ideal for the needs you've described.

The Sony is slightly more powerful with a bigger hard drive and additional USB port, but in terms of performance you may not find the difference makes that much difference to you. I've also heard some people have issues with poor viewing angles on the screen and a short battery life.

If you can, try both out before putting any money down but from what you've said I would stick with the free Acer laptop.

No, not really. Not unless I want to spend a lot more. The thing is, that I'm not meant to move it outside of my house anyway (my disability is of the mobility type) so the battery life doesn't matter. Would the processing difference translate into a major difference in speed? Also, the reliability...it would be good if it never had any issues but if it does I'm completely covered by DSA, who have people come to my house to fix it. Do graphics make a difference to movies? Thanks!